Pneumatic discharge swab



l Nov. 24, 1931. H. w. FLETCHER PNEUMATIC DISCHARGE swAB Filed Nov. 3,1924 IMM EN @@w @Mo-m @Houma Patented Nov. 24, 1931 i errar cria mom) w.FLETCHER, or HoUs'roN, TEXAS, Assienon. :ro mismas Toor. contr,4

OF HOUSTON, TEXAS, A CORPORATION OF TEXAS IPNEUMATIQ DISCHARGE SWAIBApplication led November 3, 1924. :Serial No. 747,631.

which comparatively large quantities of liquid may be draw-n from thewell without the usual wear and clogging ofthe apparatus ldue to sand.

' ,Another object is to provide means forexpelling repeated charges ofoil from an oil well bypneumatic pressure inl such manner that the sandand other impurities will be carried forcibly out with the charge ofliq- A uid, thus allowing the oil to flow freely into the well hole fromthe producinglstratum.v

Another object is to provide mechanically controlled means forregulating the 4discharge of the swab and liquid from the well,

when the .proper pneumatic pressure is ob, tained. It'is desired therebyto raise the liq` uid'from the well with force, so that the sand andother impurities will be cleaned from thel I well by the operation ofthedevice.

` y -Another object is to provide a swab plun g- -openjwhenthe plunger.is descending and erandV cooperating mechanism, .whereby the plungervalve may be automatically held .closed when said plunger is rising.

# j Referring t'oth drawings, herewith, Fig.

j. Other'objects and the means by which they arey accomplished willV beclear from the-more detailed description which followsz' i `1 is acentral longitudinal section through a device embodying'my invention:Fig. 2 is a similar view showing the parts in diilerent position. Y Fig.3 is a central longitudinal sec-V tion of the swab piston and itssupport. `Like 4 4numerals'of reference are employedto designate likeparts in all the views. f

In carryingout my inventionI employ a v` casing 1 of ordinaryconstruction within the wells, the joints of the casing being made uptightly so as to make .theI same fluid tight.y The upper end ofthecasing is threaded for. engagement with the casing head 2, having aylaterally branchedpipe thereon to allow the entrance'of air or gas onpressure.

The upper end of the casing head is provided with a stung box, includingpacking 4:, which is compressed thereon by al gland 5, which v isclamped in adjusted position bolts 6. l

The tube7 is fitted within the stuiii'ng box, thus provided, andprojects downwardly into the well to the level desired. This tube may beof ordinary tubing or drive pipe, such as I contemplate employingapacker 130i any ordinary constructionL to close the space between thetube 7 and the casin at a point within thetubing, but will limit itsupward movement within the chamber between the tubing and the casing.Spaced .above the packer is a coupling 12, connected Vwith the packer13,' by the pipe 14. Its upper end is v threaded for connection with thetube 7, and said tubing is perforated at 17 immediately aboye thecoupling. lSaid coupling 12 has an below the level of the-liquid wit inthe well.' This-will allow the liquid to pass upwardyinner flange 15forming va seat for the coiled spring 16, which serves as 'a' supportfor the l shoe 18, The spring surrounds the lower en'd of the said shoeand bears against a radial Harige 19 fitting loosely within the tubing.

-T e swab p iston20 is designedto normally rest upon the flange 19, andsaid piston is therefore. open at the lower end, and tele scopes overthe upper end` of shoe 18 as shown in Fig. 3. The piston is cylindricalin shape having its upper end closed except for the downwardly beveledopening 21,.forming a seat for the valve head 22,'shape'd to lit there``on. The said valve hasa downwardly ex- -tended .stem litted through adiametrical guide 25, and having the head 26 at its lower end. It isheldresiliently upwardly within its seat by means of a compressionspring 24.

The upper end of the valve is provided with a pin 23, adapted to contactwith the s top pm 11 of the tubing cap previously described.

The lower head 26 ofthe valve is provided with upper shoulders thereonto engage with latching dogs, a pair of which is shown 1n position belowthe guide 25v pivoted to arms 32, which extend downwardly from theguide. The upper ends of the dogs are extended iiiwardlv and haveshoulders 28 thereon to engage above the head 26. The lower ends of thedogs are provided with beveled cam faces 29 which act to engage with theinclined surface 31 at the upper end of the shoe 18 and thus to beforced inwardly by the downward movement of the plunger. The spring 30between the lower ends of the two dogs is under compression. and tendsto force the lower ends of the dogs outwardly.

The openings 17 in the tubing are normally closed by means of a sleevevalve 33, tittlng closely around the tubing and of sufficient length toclose all of the openings in the tubing. This sleeve is secured at itsupperend to a cable or wire 34, which is carried upwardly to the surfaceand passes outwardly through `a stufling box in the casing headcomprising packing 35, of compressible material held in place by athreaded plug or gland 36. This wire may be raised and lowered bymechanically operated means connected with the upper end 37 at thesurface.

In operating this device, the tubing will be installed at the desireddepth below the level of. the fluid in the well, so that the pro er loadabove the piston may be obtained. he packer will be constructed toentirely close od the passage of fluid between the tube and the casing.The iston will then rest upon the support provi ed by the shoe 18 andwill be in position above the openings4 17 in the tubing. The valve 33,will be lowered into position to close said openings 17. Air or gasyunder pressure will then be` introduced through inlet pipe 3 and willbe forced into the chamber between the tube and casing until thepressurehas reached a predetermined value. This pressure will besufficient to raise the piston and the load of oil above it. The

valve 33 will then be raised by means of wirel 34 to allow thecompressed air or as to enter the openings 17 and lift the piston andits load of oil upwardly to the surface. The bubbles of air will passlupwardly through the shoe 18, exerting a lifting pressure within thepiston, raising it with its load free of said shoe.

When the piston is in its normal position, the dogs 27 will bedisengaged from the valve and the spring 24 will hold the valve firmlyin its seat. The upward pressure of air will then force the piston andload of oil above i it upwardly to discharge the oil from the pipe 9,after which the piston' will be pro- Jected upwardly into the nipple 8,the pin 23 upon the valve contacting with the stop pin 11, throwing thevalve downwardly so that the latching dogs 27 may engage above the head26 and automatically hold the valve 1n vlowered position so that thepistonmay drop back to its original position upon thesupport 18. Afterthe piston has passed the opening provided by the discharge pipe 9, thecompressed air or gas will also be partially exhausted lowering thepressure within the tubing and also to a certain extent within thecasing. 'lhe valve may then be dropped quickly to close openings 17 andallow the pressure within the casing to again build up to the desiredamount.

When the load of oil has been discharged and the air within the tubinglowered to approximately atmospheric pressure, the oil within thelowerend of the tubing will surge upwardly therein to its original positionindicated at 38 inthe drawings. The piston will automatically adjustitself to its original p0- sition immediately above the openings 17, thevalve 22 closing automatically, and when the pressure has reached thedesired amount, a repetition of the previous discharge operation may beperformed.

' 1t will be noted that the pressure of air in the casing may beregulated as desired. After the load of fluid above the position isdecreased, owing to the lowering of the'oil in the casing may be lessthan under original conditions when the fluid is higher in the well. Asthe load above the piston thus gradually decreases, the operation may beaccomplished by raising valve 33 whenever the air or gas pressure issufficient to raise the loadl above the piston. The advantages of thistype of de vice liesin the fact .that the load of oil may be dischargedabruptly from level in the well, the amount of pressure withl the wellwith some force so that the sand or sediment will not tend to lodge inthe well.

Furthermore, there will be very little wear 4 between the swab pistonand the tubing.'

This will be due to the fact that the pressure above and below thepiston will be approximately equal therebyovercoming the tendency of thesand and sediment to settle about the piston and cause excessivefriction. The action of the discharge of the oil from the well is notmaterially different from the action of an air gun, each charge of oilbeing discharged outwardly with some force as the piston is projectedupwardly so as to engage the stop pin and throw thel latch and `valveinto open position. f

Further advantages of the invention :will be apparent to those skilledin the art Witheout further description. What I claim as new and desireto protect by Letters Patent ISI 1. In a device of the characterdescribed,

l space between the casing and tubing, said tubing having openingstherein above said packer, a mechanically controlled valve normallyclosing said openings, a swab piston in said tubing above said openings,means to allow inlet of' compressed air to said easing below said pistonto force said piston upwardly,

' land means to allow exit of oil from said tubing. y

2. In a device of the character described, a well casing, atubing insaid casing, a-packer in the well closing the space between tubing andcasing, said 4tubing having openings therein above said packer, a sleevevalve closing said openings, a swab pistonv in said tubing above saidopenings, means to allow inlet of compressed air to said casing belowsaid piston to force said piston upwardly' and means to operate saidvalve for the purpose described. A o

3. In a deviceof the character-described a well casing, a tubingtherein, means to close the space between said tubing and casing at theupper end thereof, a packer between said tubing and casing at. a pointbelow the oil level inthe well, 'said tubing having valve controlledopenings above said packer, a

' -swab piston in said tubing above said openings and means wherebycompressed air may be forced into'said casing to move said pistonupwardly in said tubing for the purpose described.

4. A pneumaticA well swab comprising a Y casing,'a tubing therein, meansclosing the upper .end of said casing, a packer between said tubing andcasing below the liquid level in the well, there being openings in saidtubing above said packer, a piston in said tubing above said openings,means to allow alr pressure to be exerted 1n said casing and means tocontrol the entrance of air from said casing to said tubing through saidopenings to move said piston upwardly in 'said tubing to the surface'.

5. A pneumatic well swab comprlsing a casing, a tubing therein, a packerclosing the space between said casing and tubing at a point below theliquid level, means closing the upper end of said casing, a piston insaid tubing abovelsaid packer and mechanically controlled means o n saidtubing ,to admit air piston to move said 'tubingto the surface.

In testimony whereofJI hereunto aix my signature this the 23dday ofOctober, A. D.

under pressure into s aid tubing below saidpiston upwardly in said

